Ventilating exhaust fans, such as those typically installed in bathrooms, draw air from within an area and pass the exhausted air out to another location, such as through a vent in the gable or roof of a home or other building structure. The exhaust fan is usually positioned adjacent an aperture in a wall or ceiling, and secured in a number of conventional manners, such as by being attached to wall or ceiling joists, or by being attached to another other structure in the wall or ceiling. Centrifugal exhaust fans typically include a rotating fan wheel having a plurality of vanes that create an outward airflow which, in turn, is directed out of an outlet opening. The fan wheel is typically coupled to a motor supported within the fan housing, and the motor drives the fan wheel, thus providing ventilation to an area. In some cases, a curved fan scroll is employed to channel air around the fan, and can be defined by a housing wall of the fan or by a separate element within the fan housing. During operation, most modern ventilating exhaust fans do not run silently. The noise emission and audible noise can depend on a variety of factors, including but not limited to the size and type of motor, the fan wheel and/or scroll design and the size, and shape of the ventilation inlet and outlet.